Sikau JavaScript · Day 34 · about 30 min
Asking questions of a list
find, includes, some, every, reduce.
Questions, answered
"Is there any milk?" "Did everyone pay?" "What's the total?" Arrays can answer questions like these in one line each.
find, some, every
const ages = [14, 22, 9, 31];
console.log(ages.find((a) => a >= 18));
console.log(ages.some((a) => a < 10));
console.log(ages.every((a) => a > 5));
The rest of this lesson
- reduce: boil it downexplain
- Tracing reduceexplain
- Predict the outputpredict
- Which method answers it?match
- Your turnwrite code
- Challengechallenge
- Badge quizquiz
- What you learnedrecap
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